Quarkus

Introduction

Quarkus is a Java framework optimized for cloud, serverless, and containerized environments. Quarkus leverages a Kubernetes Native Java stack tailored for GraalVM & OpenJDK HotSpot, which further builds on various Java libraries and standards.

Localstack is supported by Quarkus as a Dev service for Amazon Services. Quarkus Amazon Services automatically starts a LocalStack container in development mode and when running tests, and the extension client is configured automatically.

Getting started

In this guide, we will demonstrate how you can create a service client for creating and managing Lambdas on LocalStack. The Lambda extension is based on AWS Java SDK 2.x.

Prerequisites

• LocalStack installed and running
• JDK 17+ with JAVA_HOME configured properly
• Maven 3.8.1+
• Docker

Create a Maven project

Create a new project with the following command:

$ mvn io.quarkus.platform:quarkus-maven-plugin:3.6.3:create \
    -DprojectGroupId=org.acme \
    -DprojectArtifactId=amazon-lambda-quickstart \
    -DclassName="org.acme.lambda.QuarkusLambdaSyncResource" \
    -Dpath="/sync" \
    -Dextensions="resteasy-reactive-jackson,amazon-lambda"
$ cd amazon-lambda-quickstart

The above command generates a Maven project structure with imports for RESTEasy Reactive/JAX-RS and Amazon Lambda Client extensions.

Configure Lambda Client

Both Lambda clients (sync and async) can be configured through the application.properties file, which should be located in the src/main/resources directory. Additionally, ensure that a suitable implementation of the sync client is added to the classpath. By default, the extension employs the URL connection HTTP client, so it’s necessary to include a URL connection client dependency in the pom.xml file:

<dependency>
    <groupId>software.amazon.awssdk</groupId>
    <artifactId>url-connection-client</artifactId>
</dependency>

If you want to use Apache HTTP client instead, configure it as follows in application.properties:

quarkus.lambda.sync-client.type=apache

Add the following dependencies to the pom.xml file:

<dependency>
    <groupId>software.amazon.awssdk</groupId>
    <artifactId>apache-client</artifactId>
</dependency>

To configure LocalStack, add the following properties to the application.properties file:

quarkus.lambda.endpoint-override=http://localhost:4566 

quarkus.lambda.aws.region=us-east-1 
quarkus.lambda.aws.credentials.type=static 
quarkus.lambda.aws.credentials.static-provider.access-key-id=test-key
quarkus.lambda.aws.credentials.static-provider.secret-access-key=test-secret

Package the application

You can package the application with the following command:

$ ./mvnw clean package

You can further run the application in dev mode with the following command:

$ java -Dparameters.path=/quarkus/is/awesome/ -jar target/quarkus-app/quarkus-run.jar

$ ./mvnw clean package -Dnative.

Supported extensions

• Lambda
• S3
• SSM
• SQS
• SNS
• SES
• Secrets Manager
• KMS
• IAM

Configuration

The following configuration properties are fixed at build time. All the other configuration properties can be overridden at runtime.

Specific configuration

Dev Services can support specific configurations passed to the LocalStack container. These configurations can be globally applied to all containers or specified individually per service.

quarkus.aws.devservices.localstack.image-name=localstack/localstack:3.0.3
quarkus.dynamodb.devservices.container-properties.DYNAMODB_HEAP_SIZE=1G

Additional services

To start additional services for which a Quarkus extension does not exist or is not imported in the project, use the additional-services property:

quarkus.aws.devservices.localstack.additional-services."kinesis".enabled=true
quarkus.aws.devservices.localstack.additional-services."redshift".enabled=true